Disappointment. That's all I have to say about the new PX680 film (for 600 series cameras). I grabbed up a couple of packs as soon as it was released. After seeing the SX-70 color film, I assumed this would be just as great. It's so yellow and grainy. Sort of like the world has jaundice. It's possible that the film got too hot sitting in the mailbox all day, but I don't know.
It's definitely not pretty. Some of the images that I've taken will bring out red, but it's as if blue doesn't exist. So, my advice is this: If you're unsure of something, only buy one. Don't be a fool like me and buy two.